diff --git a/regress/modify.c b/regress/modify.c
index 6c4dd3d..ae49c6b 100644
--- a/regress/modify.c
+++ b/regress/modify.c
@@ -783,6 +783,7 @@
     if (fwrite(buf, zst.size, 1, fp) < 1) {
 	fprintf(stderr, "fwrite failed: %s\n", strerror(errno));
 	free(buf);
+	fclose(fp);
 	return -1;
     }
     free(buf);